Fuels for internal combustion engines



United States Patent 3,341,310 FUELS FOR INTERNAL COMBUSTION ENGINESErnst Drouven, Verona, Italy, assignor to Torrimetal Trust, Vaduz,Liechtenstein No Drawing. Filed Apr. 15, 1963, Ser. No. 272,880 Claimspriority, application Austria, Sept. 26, 1958, A 6,768/58 14 Claims.(Cl. 44--69) This application is a continuation-in-part of my copendingapplication Ser. No. 842,228, now abandoned, filed Sept. 25, 1959, forMotor Fuels) The present invention relates to improved fuels forinternal combustion engines, and more particularly to a metal-containingmotor fuel which, due to its content of particular metals, in particularform, and at particular concentrations, has improved characteristics andincreases the performance of gasoline (spark ignition) or diesel(compression ignition) engines operated therewith.

In the present specification and in the appended claims, the term motorfuel is used to designate all liquid hydrocarbon fuels suitable for usein internal combustion engines of all type, including gasoline,kerosene, and diesel fuel. Such fuels are composed of a mixture ofvarious types of hydrocarbons boiling within the range of about 80 toabout 800 F.

It has been proposed to improve the performance of internal combustionengine fuels by incorporating simultaneously therein lead, copper andZinc salts. In internal combustion engines operated with such fuelcompositions, deposits are formed on the cooled cylinder walls, saiddeposits acting as a seal between the cylinder wall and the piston, andthus increasing the compression pressure.

It has been found that the deposits in the engine caused by motor fuelsof this type have a substantially different effect, depending on thequantities of zinc, copper and lead compounds added to the fuel,depending on the type of such compounds, and also depending on theproportion of the lead relative to the'zinc and copper. Furthermore, ithas been found that extraordinary effects, especially in view of thesealing film between the cooled walls and the piston resulting fromcombustion residues, are produced by additionally incorporating into thefuel halogenated compounds which react in the combustion chamber withthe metals to form metal halogenides.

It is accordingly a primary object of the present inven tion to providea fuel for internal combustion engines which has the optimum advantagesobtainable by the named metals, especially as to the sealing effect ofthe film deposited on the cooled walls produced during the combustion ofthe motor fuel containing the additives in accordance with thisinvention.

Another object of this invention is to provide a fuel whose deposits inthe engine improve anti-knock properties.

A further object of this invention is to provide gasolines and dieselsfuels of improved combustion characteristics.

A still further object of this invention is to provide a process ofmaking improved motor fuels by the addition of a special compositioncontaining zinc, copper and lead compounds in certain amounts andproportions.

As yet another object, the present invention provides for thepreparation of concentrated solutions of the additive to be incorporatedinto the fuel.

In the preparation of copper, zinc and lead compoundcontaining motorfuels, difficulties were encountered due to the fact that thesimultaneous solubility of lead, copper and zinc salts in the commonlyused gasolines and diesel fuels is rather poor. It was thereforediflicult to provide the required concentrations of the metal additivesfor the fuel. It is of importance that the mentioned metals must be usedin the form of salts which are compatible with one another with respectto their solubility, and furthermore that in and together with the motorfuel the salts should be present in the form of a truly stable solution.For the production of the motor fuel in accordance with the presentinvention it is furthermore of great importance that the added metalcompounds are not only soluble in the concentrations intended to bepresent in the motor fuel, but also in considerably higherconcentrations.

The use of copper, zinc, and lead salts would be extremely limited if,due to an insufficient solubility of the individual compounds, the totalcommercial motor fuel would have to be mixed with large amounts ofvarious weakly concentrated solutions in excessively large stirringdevices. The desired additive solutions which can be added in relatively small volumes to the motor fuel can only be produced by usingcompounds of good solubility. Accordingly, it is necessary in order toachieve the objects of the present invention to use the metals copper,zinc and lead in the form of the naphthenates of these metals.

It is accordingly still a further object of the present invention toprovide concentrates of the metal salts of the present invention whichcan easily be added to any motor fuel without requiring special mixingdevices, and which, when added to such motor fuels, will directly resultin improved performance thereof.

With the above and other objects in view, the present invention mainlycomprises the provision of a motor fuel comprising per each liter offuel about 0.5-15 mg. of zinc in the form of zinc naphthenate, about0.5-25 mg. of copper in the form of copper napht-henate, and lead in theform of lead naphthenate in an amount at least about 2 times the weightof the sum of the zinc and copper content, the total amount of zinc,copper and lead being between about 3 and 200 mg. per liter of fuel.

It has also been found necessary in accordance with the presentinvention to provide in the composition, in addition to the abovementioned metals, a brominated and/or chlorinated hydrocarbon in anamount such as to obtain a 10% to preferably 35% to 50% bromination ofthe added metals in the case of brominated hydrocarbons, and a 20% to200%, preferably 70% to 100% chlorination of the added metals in thecase of the chlori nated hydrocarbons. The terms bromin-ation andchlorination are used herein to designate the conversion of the addedmetals into their maximum valency halogen compounds. If brominated andchlorinated hydrocarbons are used concurrently, they should be added insuch proportions as to provide the amounts of bromine and chlorinerequired for the above stated halogenation levels.

In order to achieve the optimum halogenation effect it is most preferredto use brominated benzene, brominated ethylene, chlorinated benzene orchlorinated ethylene as the halogenated hydrocarbons. Thus, bromobenzene, ethylene dibromide, ohloro benzene and/or ethylene dichloridewill give the most desirable results.

The additive composition of the present invention which contains 05-15mg. of zinc in the form of zinc naphthenate, about 05-25 mg. of copperin the form of copper naphthenate, and lead in at least double theamount of the total of the zinc and copper, the total amount of thezinc, copper and lead being greater than 3 mg., and being as high as atotal of 200 mg., are suitable not only for gasoline for internalcombustion engines, but for diesel oils and for fuels in general for alltypes of internal combustion engines.

A preferred motor fuel in accordance with the present inventioncomprises per each liter of hydrocarbon fuel about 3.5-8 mg., mostpreferably about 7.2 mg., of zinc in the form of zinc naphthenate, about0.55 mg.,

most preferably about 3.4 mg, of copper in the form of coppernaphthenate, and lead in the form of lead naph- 4 gasolines containing 3cc. of lead tetraethyl and the additives of the present invention):

Composition of the additives with reference to the metals (mg/l.)

Composition of the residues, without oxygen, sulfate and halogen(percent) thenate in an amount of about 2.5-3 times the weight of thesum of the Zinc and copper content, most preferably about 29.4 mg. oflead; and in addition a brominated and/ or chlorinated hydrocarbon ofthe type mentioned above, in an amount sufiicient for an approximately35-50% bromination or an approximately 70100'% chlorination of themetals present.

As pointed out above, the composition of the present invention has theefiect of forming a film between the cylinder walls and the piston whichimproves the compression and reduces the friction between the cylinderand piston, thus improving the entire operation of the engine andrendering the operation of the same much more economical.

While the present invention is not meant to be limited as to any theoryof how the film formation takes place, the following theory is given inthe hope that it will help others to better understand the invention. Inany event the fact is that the film mentioned above does form.

It was proved analytically that during the combustion halogenides andsulfates, as well as oxides are formed. While a portion of the salts andoxides are expelled with the exhaust gas, another portion precipitateson the cooled cylinder wall. This deposit forms a film of a certainthickness, which by the movement of the piston is constantly beingdamaged, that is by being pushed forward. On the freed parts of thecooled wall new precipitation is deposited so that the film isconstantly being formed partially destroyed and regenerated.

If the engine is opened there is found between the piston head and themotor block a porous sealing ring which is level at the top, that ispressed flat and which is about 1-2 mm. (depending on the size of theengine) wide, is conical towards the bottom and which fills the spacebetween the piston head and the motor block in a wedgeshaped manner.

This ring can be taken off and upon analysis is found to haveessentially always the same composition. Lead as lead chloride and/orlead bromide, and as lead sulfate, forms the basis of the film, whilecopper and Zinc compounds quantitatively constitute only a small portionof the deposits. The presence of these metals is, however, of criticalimportance for the formation of the film, and their amount is likewisedecisive for the formation and the efficiency of the film in accordancewith the present invention. Thus, for example, it has been found thatthe copper content influences the combustion and thereby the amount andproportion of C and H in the deposits. The content of C and H in thedeposits in order to achieve the most desirable effects has been foundto be about 30- 35%, whereby the ratio of C:H is about 1:1.

It has been found that by using the composition of the present inventionwithin the ranges set forth these results are achieved.

Using gasolines with the additives of the present invention it has beenfound that varied compositions of the additive with reference to thenaphthenates, to a certain degree independently of the used fuel, givethe following combustion residues (the following analyses were made onresidues from motor fuels which were formed with It may thus be seenthat the amounts of metal additives used in accordance with the presentinvention are critical for the achievement of the desired effects.

It has been found that the addition of less than about 0.5 mg. of zinc,about 0.5 mg. of copper, and less than about 2 mg. of lead does notproduce any effect at all, or precisely, does not result in theimprovements obtainable in accordance with the present invention. On theother hand, if the zinc content of the fuel is too high, undesirable andeven harmful deposits are formed in the combustion chamber. Furthermore,gasolines containing too high an amount of zinc tend to knock. Too highan amount of copper does not result in undesirable deposits in thecombustion chamber, but causes an excessive increase in the compressionpressure due to the formation of a seal which prevents the necessarylubrication by an oil film on the cylinder wall.

The necessity of a large amount of lead is also shown by the aboveanalyses of the combustion deposits.

The additives of the present invention may be added not only to unleadedfuels, but also to leaded motor fuels, that is fuels containing solublelead compounds, particularly lead tetraethyl, as anti-knock agents. Itis common practice to use in conjunction with lead tetraethyl certainhalogenated hydrocarbons as scavenging agents. In the normal leadedmotor fuel the contents of lead tetraethyl and halogenated hydrocarbonsare balanced in such Way that in the combustion chamber theoreticallythe total amount of lead becomes volatile as lead-bromide or leadchloride, and is expelled with the exhaust gases.

In order to obtain a complete reaction between the lead and the halogenof the added halogenated hydrocarbon it has been suggested that thehalogenated hydrocarbon be present in an excess. Thus, for example, thefollowing two preparations are available on the petroleum market underthe name of Ethyl fluid:

1 T-Fluid or Aviation-Octyl for airplanes Motor-Mix or Motor'O ctyl forautomobiles Despite the excess of halogenated hydrocarbon experience hastaught that on running the engine with the leaded gasoline a residue oflead oxide precipitates on the piston head, which means that the desiredreaction was not complete because of the incomplete reaction of the leadwith the halogenated hydrocarbons.

The combustion residues which are formed from normal lead-containinggasoline and which are deposited at the piston heads and the motor headreduce the size of the combustion chamber and thus increase thecompression undesirably. However, it is impossible to observe an in-'about 350 F. and about 800 crease in the sealing which should bedetermined by the reduction of the quantity of the amount of gas blownthrough. On the contrary, the undesirable incrustation causes a gummingup of the piston rings, the latter becoming stuck, and thereby reducingthe sealing. Thus, residues of ordinary lead-containing gasoline cannotbe compared with the sealing film and with the ring formation of thepiston head which is achieved with the additive composition of thepresent invention, which leaves the piston rings freely mobile and whichincreases the compression simultaneously reducing the incrustation andthe amounts of gas blown through.

Although by the use of an excess of the halogenated ydrocarbon and evenin cases of complete reactions of the lead with the halogenatedhydrocarbon which is present in a large amount, it has been foundpreferable in the case of moderately leaded gasoline not to change theabove indicated amount of chlorine and/ or bromine hydrocarbon. Only inthe case of very strongly leaded gasoline can the addition ofhalogenated hydrocarbon be omitted. The omission is possible in the caseof an addition of at least 0.3 cc. of lead tetraethyl per liter and canunconditionally be recommended in the case of 0.6 cc. of lead tetraethylper liter.

In the case of heavily leaded gasolines an amount of lead remainsavailable for the formation of the desired film. It has thus beendetermined that with an addition of at least 0.3 cc. of lead tetraethyland more, it is sufficient if instead of double the amount of lead, withrespect to the amount of copper and zinc, that the amount of added leadbe 80-100% of the total amount of the copper and zinc.

In the examples given below the effects of the additives according tothe present invention are shown, when adjusted with respect to leadedgasoline.

Gasoline as used in connection with the present invention is a wellknown article of commerce for use in internal combustion enginesoperating on the Otto cycle. It is composed of a mixture of varioustypes of hydrocarbons, including aromatics, olefins, parafims,isoparafiins and naphthenes. These mixtures are obtained from petroleumby refining processes including fractional distillation, catalyticcracking, hydroforming, alkylation and extraction. Motor gasoline boilsbetween 80 F. (initial boiling point) and about 450 .F., when tested byA.S.T.M. method 86. Its vapor pressure by A.S.T.M. method D323 variesfor use at different seasons between 7 and 15 lbs. per square inch at100 F.

Among the diesel fuels used in the practice of the present invention areall of the commonly sold grades including kerosene. Kerosenes normallyhave boiling ranges between 100 F. and about 600 F. and are sometimesreferred to in the petroleum industry as No. 1 fuel oils. Diesel. fuelsin general have boiling ranges between F. and are described more fullyin A.S.T.M. specification D-975-53T as amended.

Such fuels are derived from petroleum crude oils by a variety ofprocessing operations which may include atmospheric and vacuumdistillation, catalytic and thermal cracking, catalytic and thermalreforming, visbreaking, hydrotreating and the like. Like gasolone,diesel fuel is composed of a mixture of various types of hydrocarbonsincluding parafiins, isoparafiins, naphthenes and aromatics.

In the case of the production of motor fuels in accordance with thepresent invention, where the motor fuel contains more than 1% sulfur,the efliciency in accordance with the present invention can be impairedthrough acids of the sulfur formed during combustion, Which partly bindamounts of metals added. In such cases, the amounts of metals added inaccordance with the present invention should be increased according tothe content of sulfur, e.g. the content of sulfur of 2%, the

amounts of the metals (zinc, copper and lead) should be doubled.

The following examples are given to further illustrate the presentinvention. However, the scope of the invention is not meant to belimited to the specific details of the examples.

The following examples were carried out with naphthenates of copper,lead and zinc. For the preparation of the required master solutions,commercial naphthemates of lead, copper and zinc made by HoechsterFarbwerke, Frankfurt-am-Main, were used. These naphthenates wereindividually dissolved in a gasoline having a boiling range of 100 C. insuch amount as to obtain (1) a lead solution containing 58.8 g. of leadper liter, (2) a copper solution containing 13.6 g. of copper per liter,and (3) a zinc soluton containing 28.8 g. of zinc per liter.

EXAMPLE 1 50 cc. of the lead solution, 25 cc. of the copper solution and25 cc. of the zinc solution were mixed with 3.0 cc. of mono bromobenzene and the resulting solution was mixed with liters of commercialunleaded gasoline (DEA=Deut-che Erdol A.G., Hamburg, Production1955/56). The gasoline contained 29.4 mg. of lead, 3.4 mg. of copper,7.2 mg. of zinc and 0.03 cc. of mono bromo benzene per liter.

Bench test experiments with 9. Fiat 1100 engine operated on this fuelshowed, after running the engine for 20 hours at 2500-3000 r.p.m., amaximum performance of 31 H.P. in contrast to 30 H.P. observed when theengine was operated on the same gasoline not containing the additives ofthis invention. Furthermore, there was found a decrease in the fuelconsumption from 246 g./H.P./h. to 231 g./H.P./h. at 2500 rpm. At otherr.p.m. values, similar savings in fuel consumption could be obtained.

The amount of gas blown through into the crankcase was substantiallyreduced and stabilized at a minimum, which was measured and found to be50% of the amount of gas blown through and measured when the same motorwas operated without the additive of the present invention. The amountof gas blown through with standard gasoline was measured to be 88 cc.per second at 3000 r.p.m. and 11.6 H.P. output, and this blown throughamount dropped for the same number of revolutions and the same output to44 cc. when the gasoline with the additive of the present invention wasused. At 2500 r.p.m. and 6.7 H.P. the amount of gas blown throughdropped from 60 cc. to 30 cc.

The increase of the output or efiiciency corresponded to the improvedsealing effect obtained according to the present invention and to acorresponding increase of the compression pressure with a simultaneousimprovement of the combustion. In the exhaust gases a drop of the COpercentage and an increase of the CO percentage was found. Irrespectiveof the increased compression pressure, no tendency to knock could bedetermined or found.

EXAMPLE 2 25 cc. of the lead solution, 12.5 cc. of the copper solution,and 12.5 cc. of the zinc solution were mixed with 0.935 cc. of ethylenedibromide and the mixture was added to 50 litres of the gasoline ofExample 1. The additives thus contained with respect to the metalcontents the same composition as in Example 1. However, the ha1ogenof0.0187 cc. of ethylene dibromide instead of 0.03 cc. liter.

Bench test experiments with this fuel were carried out with the sameFiat 1100 engine as in Example 1. After the test described in Example 1the engine was operated on the fuel containing the above additives for 1hour. The maximum performance remained at 31 H.P. as in Example 1, withthe tendency however, to be slightly greater. The fuel consumpton at2500 revolutions per minute fell from 231 g./H.P./h. to 213 g./H.P./h..Asimilar decrease was observed at other r.p.m. values.

of mono bromo benzene per The composition of the exhaust gases was aboutthe same as in Example 1. The same applies to the gas pressure in thecrankcase and to the compression pressure. Likewise, no tendency of theengine to knock was found.

EXAMPLE 3 The additive mixture described in Example 1 was added to 100liters of commercial diesel fuel of the following characteristics:

The diesel oil had a specific weight of 0.840 and a sulfur content of0.96%.

Using this fuel tests were carried out in a 1953 Borgward dieselpassenger car (1800). After a relatively short driving time (distancecovered 50 km.) a marked improvement in engine performance manifesteditself in a considerable increase of the accelerating power and also abetter climbing power in mountainous terrain. When go ing up hills, theincrease in engine performance always made it possible to use a highergear than previously.

After driving the car over a distance of 30,000 km. the engine wasopened up and no residues were found. The increased performance and thedecreased fuel consumption remained at the same good levels afterdriving the car for an additional 20,000 km.

EXAMPLE 4 An additive was added to 50 liters of the same diesel oil asin Example 3 so that the composition with respect to the metals was thesame as in Example 3. However, the addition of the halogenatedhydrocarbon amounted to 0.045 cc. and in another case to 0.06 cc. ofmono bromo benzene per liter.

Road tests were conducted with the same Borgward diesel car as used inExample 3. The increase in engine performance rose to twice the amountobserved in the test of Example 3. This was apparently due to theincrease of the halogen addition by 50% and by 100% respectively. Theincreased efliciency was particularly observable in connection with theincrease of accelerating power and thereby covercoming thecharacteristic sluggishness of diesel engines.

EXAMPLE 5 The following test was carried outwith unleaded ARAL Supergasoline to which per liter of fuel were added 29.4 mg. lead, 0.6 mg.copper and 3.6 mg. zinc, and furthermore 0.006 cc. ethylene dibromideand 0.011 cc. ethylene dichloride, whereby corresponding amounts of theabove described master solutions of the respective metals were used.

Using this gasoline tests were carried out with a Topolino (Fiat 500A)motor car, model year 1948. This car was run 200,000 km. with thegasoline containing the additive described above, according to theinvention. The engine was over-hauled only once after having been run119,000 km.

After 200,000 km. the car was run with normal gasoline, that means withgasoline without the respective additive, and it was observed, that themotor performance decreased progressively. Finally the motor could movethe car only on a level road at a maximum speed of 55 km./ h. Already ata 2% inclination it was necessary to change into second gear. Afterrunning in this way the gasoline with the additive of the presentinvention was used again and surprisingly it was found that aftertravelling for only a few kilometers the motor regained. progressivelyits former performance.

The care would take any inclination of up to 5% in highest gear and themaximum speed on level terrain was increased to 90 km. per hour. Thisperformance remained the same with the gasoline containing the additiveaccording to the present invention upon further running with the samemotor. This effect is therefore clearly based on the use of the gasolinewith the additive of the present 5 invention.

EXAMPLE 6 16 cc. of the lead solution, 25 cc. of the copper solution and25 cc. of the zinc solution were added to 100 liters of commercialgasoline which had been leaded with 10 0.3 cc. per liter of leadtetraethyl. The gasoline has the following characteristics: Specific wt.at C. 0.726 Initial boiling 32 15 Boiling until 55 percent 14.5 Boilinguntil 70 do.. 31 Boiling until 100 do 55 End of boiling 192 Olefincontent percent 21 Aromatic content do 15 Each liter of the gasolinethus contained 9.4 mg. of lead, 3.4 mg. of copper and 7.2 mg. of zinc.

Using this fuel test drives with a Leoncino bus (spark plug engine of2.545 liters capacity) produced by the O.M.-Works Brescia (Italian Fiatgroup) were taken. The bus carried a load of 5000 kg. The test distanceamounted to 201 km. and was covered nine times at the same average speedof 52.5 km. per hour.

The first drive was taken with a regular gasoline not containing theadditives of this invention. The fuel consumption amounted to 25.746liter/100 km. The following eight drives were taken with the abovedescribed gasoline according to this invention and gave the followingresults:

Fuel consumption in liters Total Per 100 km.

2d Drive (1st; Drive was taken without additives) 48. 300 24. 029 (1Drive 920 22. 845 43. 900 21. 840 44. 630 22. 203 43. 310 21. 547 40.000 19. 900 38. 880 I9. 343 38.300 19. 054

As may be seen from these data, the fuel consumption decreased by 25.99%after going a total distance of 1608 km. as compared with the fuelconsumption observed when operating the bus on a regular fuel withoutthev additives of this invention.

EXAMPLE 7 A gasoline containing 0.45 cc. per liter of lead tetraethyland having the following characteristics:

Specific wt. at 15 C. 0.731 Distillation range, C. 35-196 Content ofolefins percent 21 Content of aromatics do 12 was mixed with 0.6 mg. ofcopper, 7.2 mg. of zinc and 6.2 mg. of lead per liter, all three metalsbeing in the form of their naphthenates.

This was achieved by taking from the master solutions 105.5 cc. of thelead solution, 44.1 cc. of the copper solution and 250 cc. of the zincsolution, mixing the solutions with each other, and then adding theresulting mixture to 1000 liters of the gasoline.

Using the gasoline containing the additives tests were carried out witha Fiat motor 1100-103 which had been run 50,975 km. with normalgasoline. In a first test series the motor was run in worn condition,and in a second series after a general overhaul. In both casesmeasurements were taken with full load and partial load.

75 The following tables give the percentage difference came soft andeasily removable. On the motor head there was practically no residue andthe piston rings were free of residue and freely movable.

EXAMPLE 8 8 cc. of the lead solution, 12.5 cc. of the copper solutionand 12.5 cc. of the zinc solution were mixed with 100 liters of acommercial leaded super gasoline con- Table I [Percentage changes ofmeasurements indicating the engine performance when using gasolinecontaining the additive of the present invention as compared to the useof normal gasoline] Measurements at full load Revolutions Before theoverhaul After the overhaul per minute Performance, Specific Amount ofgas Specific Amount of gas Horsepower percent consumption, blownHorsepower Performance consumption, blown percent through, percentthrough, percent percent Table 11 Measurements with partial loadRevolutions per Before the overhaul After the overhaul minutePerformance, Specific consump- Amount of gas Specific consump- Amount ofgas Horsepower percent tion, percent blown through, Horsepower tion,percent blown through,

percent percent Table III taining 0.6 cc. of lead tetraethyl per liter,and having WITH NORMAL GASOLINE the following characteristics;

' 0 Specific Amount MW 50 pwfi W a 15 C w- 0.739 Tests Revolutionsconsumption, blowri1 Olefin C t nt percent 14.2 permlnut gJ J gagBoiling range 32197 For mass testing purposes the gasoline containin theFull load with worn 4,000 268 400 g engim 3,000 273 292 additives wasutilized in the vehicles of a large industrial Partimoad after 3 500 247132 enterprise which owned passenger cars and trucks, and overhauL 2:000334 62 whose total consumption of the gasoline was three million liters.WITH GASOLINE CONTAINING THE DD E Based On spot examinations there wasfound to be a reduction in gasoline consumption amounting to Full loadwith Worn 4, 000 259 280 14.78%. The reduction in gasoline consumptionwas more englne. 3,000 266 142 pronounced in trucks than in passengervehicles and Partial load after 3, 500 232 70 varied, depending on thediiferent types of engines, beoverhaul. 2,000 300 36 tween 7 and 20%. Ingeneral an increase in the accelera- With respect to the appearance ofthe motor before and after the use of the gasoline containing theadditive of the present invention the following should be noted. Theused motor exhibited before application of the invention an incrustationof approximately 1.5 mm. on the piston head and on the motor head. Thisincrustation was black and hard, that is a typical oil crust. Theresidue was left in the engine when the gasoline with additives wasintroduced into the engine. After the test with the gasoline containingthe additive the incrustation on the piston head was reduced to about0.2 min; it be- EXAMPLE 9 17.5 cc. of the lead solution, 4.5 cc. of thecopper solution and 12.5 cc. of the zinc solution, 0.3 cc. ethylenedibromide and 0.6 cc. ethylene dichloride were added to of one of thecommon Volume percent Content of olefins 3 Content of aromatics 30:9Content of paraifins and naphthenes 66.0 Content of sulfur 0.034

To the leaded commercial gasoline therefore per liter were added 10 mg.lead, 0.6 mg. copper, 3.6 mg. zinc, 0.003 cc. ethylene dibromide and0.006 cc. ethylene dichloride.

The following bench tests were carried out with this gasoline using aDaimler-Benz motor M121, Mercedes engine type 180b. The motor was afactory new motor and tuned mechanically so as to be in the bestpossible condition. This motor was run before the test for 100 hours onthe test bench thus reaching its mechanical peak condition and excludingalso any improvement in the performance by mechanical means. Havingrecorded the performance diagram and amounts of gases blown throughwithout the use of the additive, the engine was then run for 36 hours onthe bench with gasoline containing the invention additives, in order tobuild up the metal salt film. After that the performance diagram and theamount of gas blown through were recorded, relating to the use of theadditive.

Running the engine on gasoline with additive it was found that with thesame amount of engine fuel a longer running time according to theprescribed test program was made possible, amounting to between 2.1 andan increase of the possible running distance between 2.4 and 4.6%, and adecrease of the fuel consumption (related to a comparative distance of100 km.) between 2.3 and 4.3%. Based on further tests a decrease of fuelconsumption between 2.3 and 6.2% was found, when compared with resultsobtained without the additive. The figures obtained show that theresults of the comparative measure ments of the fuel consumption withand without additive are in their values well outside the :l% scatteringlimits obtained with unaltered fuel.

Related to the specific running conditions of the engine using purecommercial gasoline and the measured amount of gas blown through, adecrease of the amount of gas blow through was found, when usinggasoline containing the additives of the present invention under thesame specific running conditions. The scattering limits of themeasurements were 12%, the average percentual decrease rose with risingoil temperature and rising cooling water temperature and reached at 80C. a figure of 13%. Although it is known, that the results obtained whenmeasuring the amounts of gas blown through tend to oscillateconsiderably, a distinct decrease within this scattering limit of theamounts of gas blown through was found, when the engine was operatedwith gasoline containing the additives according to the presentinvention.

EXAMPLE in the Examples 1-9 were also Daimler-Benz The effects describedfound in the following bench tests, using a motor 180b.

For the test a super gasoline containing 0.59 cc. per liter leadtetraethyl preparations with an excess content of halogenatedhydrocarbons as scavenging agents was used. The gasoline had thefollowing characteristics:

Spec. wt. 0.746 Boiling range, C. 34-196 Boiling to 100 C. percent 46Content of olefins do 42 Content of aromatics -do 14 Content of benzenedo 0 NO. Research 99.5 NC. Motor 87.2

To this gasoline as additive per liter were added in the form ofnaphthenates: 9.4 mg. Pb, 3.4 mg. Cu, 7.2 mg. Zn.

A special addition of halogenated hydrocarbons could be omitted becauseof the excess of scavenging agents in the lead preparation.

After an adequate operating period the full effect according to thepresent invention was revealed.

Summing up it may be stated that comparative determinations of theconsumption for operation with and without the additive according to thepresent invention determined as described above gave, for bothexperimental series, a consumption reduction of the additive containinggasoline combined with the reduction of the blown through amounts ofgas. Reduction of consumption based on consumption without additiveamounted to between 2.3 and 6.2%, the reduction of the blown throughamounts of gas to a reduction of between 6 and 13%.

Further to the tests described in the above mentioned 10 examples, wherethe efiicacy of the additive was demonstrated at amounts according tothe present invention, other road and bench tests (af) were carried outwith gasolines containing additive, which additives although resemblingthe additive according to the present invention in their components, didnot correspond with it in the amounts of Zinc, copper or the halogenatedhydrocarbons which were added to each liter of gasoline.

For the road test series (a-d) a Fiat 500-A motor (Topolino) series 1948was used. The leaded gasoline used for these tests and containing one ofthe usual halogenated lead tetraethyl preparations had the followingcharacteristics:

Spec. wt. 0.734 Boiling range, C. 35-202 Boiling to C. percent 50Content of olefins do 21 Content of aromatics do 12 NO. Research 87.4N.O. Motor 81.0 Lead tetraethyl in cc./l. 0.43

Before the test the car was run with the same gasoline, however notcontaining the additives, for 500 km. After mechanical cleaning of themotor and after change of the motor oils, the motor was ready for thetest. More than 500 km. were driven with the gasoline containing therespective additives. The compression pressure of the cylinders 1-4 weremeasured before using the gasoline with the additives and after thetest.

(a) T est.To the above described gasoline were added as additive in theform of their naphthenates per each liter of fuel: 10.0 mg. Pb, 0.2 mg.Cu, 10.0 mg. Zn. The compression pressure measurements were thefollowing:

Before the test After 630 km.

Cylinder 1 8.6 7. 8 Cylinder 2. 7. 9 7. 4 Cylinder 3.- 8. 6 7. 7Cylinder 4. 8. 9 8. 2

Upon opening the motor after the test it was found that it was very muchsmeared and that the piston rings were sticky. The motor head was verymuch incrusted with a flake-like crust which, however, was easilyremovable. The cylinder heads 1 and 4 had hard crusts, partly flakeswhich sprang off when being removed. The cylinder heads 2 and 3,however, showed a compact, smooth ad pitch-tough incrustation.

Any formation of the sealing rings according to the invention was notfound at all.

(h) Test.-To the above described gasoline were added as additive in theform of their naphthenates per each liter of fuel: 17.6 mg. Pb, 2.0 mg.Cu, 0.39 mg. Zn.

of fuel: 9.4 mg. Pb, 3.4 mg.

Mercedes 18012 was used.

The results of the compression pressure measurements were the following:

Before the test After 500 km.

Cylinder l. 8.6 8. 2 Cylinder 2- 7.8 7. 6 Cylinder 3. 8. 6 8. 3 Cylinder4.- 8. 9 8. 6

Upon opening the motor a complete absence of the sealing ring typicalfor the invention was found. Instead (c) T est.To the above describedgasoline were added as additive in the form of their naphthenates pereach liter of fuel: 18.0 mg; Pb, 31.5 mg. Cu, 4.2 mg. Zn. The results ofthe compression pressure measurements were the following:

Before the test After 230 km.

Cylinder 8.6 10. Cylinder 2 7. 8 9. 4 Cylinder 3 8. 9. 3 Cylinder 4".--8. 8 10. 0

The test had to be broken off after the first compression pressuremeasurements were taken because the motor evidently could no longer besubjected to such excessive stress.

Upon opening the motor a thin layer of red ash was found on the pistonheads. The cylinder walls were completely dry and without any oil film.

(d) T est.--To the above described gasoline were added as additive inthe form of their naphthenates per each liter Cu, 36.0 mg. Zn. Theresults of the compression pressure measurements were the following:

Before the test After 540 km.

Cylinder 1- 8. 5 8.0 Cylinder 2 7.8 7. 6 Cylinder 3. 8.7 8. 1 Cylinder4... 9. 0 8.1

Upon running this motor, already after about 100 km. a decrease of theperformance was observed and also a frequent and violent knocking of themotor. After opening the motor soot flakes at the plugs and an unusualsooty residue were observed. Furthermore, the measurements before. theopening of the motor showed a decrease of the damaged by the content ofZinc being too high.

Forthe bench test series (e-f) a Daimler-Benz motor (2) T est.-For thisbench test described below a gasoline having the followingcharacteristics was used:

Spec. wt. 0.718 .Boiling range, C. 35-162 Boiling to 100 C. percent 66.5Contentof olefins do 26 Content of aromatics do 11 N.O. Research 89"-N.0. Motor 80 This gasoline contained only 0.15 cc. per each liter offuel of one of the usual halogenated lead tetraethyl preparations.

To the above described gasoline were added as additive per each liter offuel in the form of their naphthenates: 29.4 mg. Pb, 3.4 mg. Cu, 7.2 mg.Zn. There was no spe cial addition of halogenated hydrocarbons.

Because of irregularities which appeared during this bench test with theabove named motor and since there was no increase of performance at all,but rather a decrease of performance was observed, the motor was opened.On the piston heads was found a large amount of residues in the form ofa grey-white powder which by analysis was found to be lead oxide havinga certain content of halides. No tendency for the formation of the metalsalt film according to the invention could be 0bserved. This was due tothe fact that with the small content of lead tetraethyl preparation toosmall amounts of halogenated hydrocarbons were present.

(7) T est-For the bench test described below a gasoline was used havingthe following characteristics:

Spec. wt 0.721 Boiling range, C. 35-167 Boiling to 100 C percent 65Content of olefins do 28 Content of aromatics do 7 N.O. Research 89.3N.O. Motor 79.5

amounts of halogenated hydrocarbons as scavenging agents.

To the aforementioned gasoline were added as additive per each liter offuel in the form of their naphthenates: 29.4 mg. Pb, 3.4 mg. Cu, 7.2 mg.Zn. There was no special addition of halogenated hydrocarbons.

Neither a decrease nor an improvement of performance could positively beobserved. The motor was opened and no formation of the metal salt filmaccording to the invention could be observed. There was found, however,only a small precipitation of lead oxide which was regarded asinsignificant for the further operation of the motor. The test showedthat even with a leading of 0.23 cc. of a leadalkyl preparation per eachliter of fuel, a special addition of halogenated hydrocarbons cannot beomitted when the effect according to the invention is to be obtained.

liter,

Without further analysis, the foregoing will so fully reveal the essenceof the present invention that others can by applying current knowledgereadily adapt it for various applications without omitting featuresthat, from the standpoint of prior art, fairly constitute essentialcharacteristics of the generic or specific aspects of this inventionand, therefore, such adaptations should and are intended to becomprehended within the meaning and range of equivalence of thefollowing claims.

What is claimed as new and desired to be secured by Letters Patent is: I

1. A motor fuel for use in internal combustion engines, said motor fuelcomprising a liquid hydrocarbon motor fuel for internal combustionengines containing as an essential co-active ingredient an additive pereach liter of fuel consisting of about 05-15 mg. of zinc in the form ofzinc naphthenate, about 0.5-25 mg. of copper in the form of coppernaphthenate, and lead in the form of lead naphthenate in an amount equalto at least two times the total of the zinc and copper content, thetotal amount of zinc, copper and lead being not more than 200 mg. perand also containing a member selected from the group consisting ofbrominated and chlorinated benzene and ethylene in an amount sufiicientfor an about 10- bromination and an about 20-200% chlorination,respectively, of said copper, Zinc and lead.

2. A motor fuel for use in internal combustion engines,

said motor fuel comprising a liquid hydrocarbon motor fuel for internalcombustion engines containing as an essential co-active ingredient anadditive for each liter of fuel consisting of about 0.5-15 mg. of zincin the form of zinc naphthenate, about 0.5-25 mg. of copper in the formof copper naphthenate, and lead in the form of lead naphthenate in anamount equal to about two to three times the total of the zinc andcopper content, and also containing a member selected from the groupconsisting of brominated and chlorinated benzene and ethylene in anamount sufficient for an about 10-100% bromination and an about 20-200%chlorination, respectively, of said copper, zinc and lead.

3. A motor fuel for use in internal combustion engines, said motor fuelcomprising a liquid hydrocarbon motor fuel for internal combustionengines containing as an essential co-active ingredient an additive pereach liter of fuel consisting of about 0.5-15 mg. of zinc in the form ofzinc naphthenate, about 0.5-25 mg. of copper in the form of coppernaphthenate, and lead in the form of lead naphthenate in an amount equalto about two to three times the total of the zinc and copper content,and also containing a member selected from the group consisting ofbrominated and chlorinated benzene and ethylene in an amount sufficientfor an about 35-50% bromination and an about 7 -100% chlorination,respectively, of said copper, zinc and lead.

4. A motor fuel for use in internal combustion engines, said motor fuelcomprising a liquid hydrocarbon motor fuel for internal combustionengines containing as an essential co-active ingredient an additive pereach liter of fuel consisting of about 3.5-8 mg. of zinc in the form ofzinc naphthenate, about 0.5- mg. of copper in the form of coppernaphthenate, and lead in the form of lead naphthenate in an amount equalto about 2.5-3 times the total of the zinc and copper content per liter,and also containing a member selected from the group consisting ofbrominated and chlorinated benzene and ethylene in an amount sufficientfor an about -100-% bromination and an about 20-200% chlorination,respectively, of said copper, zinc and lead.

5. A motor fuel for use in internal combustion engines, said motor fuelcomprising a liquid hydrocarbon motor fuel for internal combustionengines containing as an essential co-active ingredient an additive pereach liter of fuel consisting of 3.5-8 mg. of zinc in the form of Zincnaphthenate, about 0.5-5 mg. of copper in the form of coppernaphthenate, and lead in the form of lead naphthenate in an amount equalto about 2.5-3 times the total of the zinc and copper content, and alsocontaining a member selected from the group consisting of brominated andchlorinated benzene and ethylene in an amount sufficient for an about35-50% bromination and an about 70-100% chlorination, respectively, ofsaid copper, zinc and lead.

6. A motor fuel for use in internal combustion engines, said motor fuelcomprising a liquid hydrocarbon motor fuel for internal combustionengines containing as an essential co-active ingredient an additive pereach liter of fuel consisting of about 7.2 mg. of zinc in the form ofzinc naphthenate, about 3.4 mg. of copper in the form of coppernaphthenate, about 29.4 mg. of lead in the form of lead naphthenate, anda member selected from the group consisting of brominated andchlorinated benzene and ethylene in an amount sufficient for an about35-50% bromination and an about 70-100% chlorination, respectively, ofsaid copper, zinc and lead.

7. Diesel fuels, boiling in the range between about 200 F. and about 600F. containing as an essential oo-active ingredient an additive per eachliter of fuel consisting of about 7.2 mg. of zinc in the form of zincnaphthenate, about 3.4 mg. of copper in the form of copper naphthenate,about 29.4 mg. of lead in the form of lead naphthenate, and about 0.045to about 0.06 cc.

- of mono bromo benzene.

8. A motor fuel for use in internal combustion engines, said motor fuelcomprising a liquid hydrocarbon motor fuel for internal combustionengines containing as an essential co-active ingredient an additive pereach liter of fuel consisting of about 3.6 mg. of zinc in the form ofzinc naphthenate, about 0.6 mg. of copper in the form of coppernaphthenate, about 29.4 mg. of lead in the form of lead naphthenate, andabout 0.006 cc. of ethylene dibromide and 0.011 cc. of ethylenedichloride.

9. A motor fuel for use in internal combustion engines, said motor fuelcomprising a leaded liquid hydrocarbon motor fuel for internalcombustion engines containing as an essential co-active ingredient anadditive per each liter of fuel consisting of about 0.5-15 mg. of zincin the form of zinc naphthenate, about 05-25 mg. of copper in the formof copper naphthenate, and lead in the form of lead naphthenate in anamount equal to at least two times the total of the zinc and coppercontent, the total amount of zinc, copper and lead in the form ofnaphthenates being between about 3 and 200 mg. per liter, and alsocontaining a member selected from the group consisting of brominated andchlorinated benzene and ethylene in an amount suflicient for an about10-100-% bromination and an about 20-200% chlorination, respectively, ofsaid copper, zinc and lead in the form of naphthenates.

10. A motor fuel for use in internal combustion engines, said motor fuelcomprising a leaded liquid hydrocarbon motor fuel for internalcombustion engines containing as an essential co-active ingredient anadditive per each liter of fuel consisting of about 3.5-8 mg. of Zinc inthe form of zinc naphthenate, about 0.5-5 mg. of copper in the form ofcopper naphthenate, and lead in the form of lead naphthenate in anamount equal to about 2.5-3 times the total of the zinc and coppercontent, and also containing a member selected from the group consistingof brominated and chlorinated benzene and ethylene in an amountsufficient for an about 35-50% bromination and an about 70-100%chlorination, respectively, of said copper, zinc and lead in the form ofnaphthenates.

11. A motor fuel for use in internal combustion engines, said motor fuelcomprising a leaded liquid hydrocarbon motor fuel for internalcombustion engines containing between about 0.3-0.6 cc. of leadtetraethyl and halogenated hydrocarbon scavenging agents therefor, andalso containing as an essential co-active ingredient an additive pereach liter of fuel consisting of about 05-15 mg. of Zinc in the form ofZinc naphthenate, about 0.5-25 mg. of copper in the form of coppernaphthenate, and lead in the form of lead naphthenate in an amount ofabout -100% of the total of the zinc and copper content, and alsocontaining a member selected from the group consisting of brominated andchlorinated benzene and ethylene in an amount sufficient for an about10- bromination and an about 20-200% chlorination, respectively, of saidcopper, zinc and lead in the form of naphthenates.

12. A motor fuel for use in internal combustion engines, said motor fuelcomprising a leaded liquid hydrocarbon motor fuel for internalcombustion engines containing per liter 0.3-0.6 cc. of lead tetraethyland halogenated hydrocarbon scavenging agents therefor in an amount upto 50% higher than necessary for halogenating the lead of the leadtetraethyl, and also containing as an essential co-active ingredient anadditive per each liter of fuel consisting of about 3.6 mg. of zinc inthe form of zinc naphthenate, about 0.6 mg. of copper in the form ofcopper naphthenate, and about 10 mg. of lead in the form of leadnaphthenate.

13. A motor fuel for use in internal combustion engines, said motor fuelcomprising a leaded liquid hydrocarbon motor fuel for internalcombustion engines containing per liter between about 0.3-0.6 cc. oflead tetraethyl and halogenated hydrocarbon scavenging agents thereforin an amount up to 50% higher than necessary for halogenating the leadof the lead tetraethyl, and also containing as an essential co-activeingredient an additive per each liter of fuel consisting of about 05-15mg. of zinc in the form of zinc naphthenate, about 05-25 mg. of copperin the form of copper naphthenate, and lead in the form of leadnaphthenate in an amount of about 80-100% of the total of the zinc andcopper content in the form of naphthenates.

14. A motor fuel for use in internal combustion engines, said motor fuelcomprising a leaded liquid hydrocarbon motor fuel for internalcombustion engines containing per liter 0.6 cc. of lead tetraethyl andhalogenated hydrocarbon scavenging agents therefor in an amount up to50% higher than necessary for halogenating the lead of the leadtetraethyl, and also containing as an essential co-active ingredient anadditive per each liter of fuel consisting of about 7.2 mg. of zinc inthe form of zinc naphthenate, about 0.6 mg. of copper in the form ofcopper naphthenate, and about 6.2 mg. of lead in the form of leadnaphthenate.

References Cited FOREIGN PATENTS 11/1955 France.

DANIEL E. WYMAN, Primary Examiner. Y. H. SMITH, Assistant Examiner.

1. A MOTOR FUEL FOR USE IN INTERNAL COMBUSTION ENGINES, SAID MOTOR FUELCOMPRISING A LIQUID HYDROCARBON MOTOR FUEL FOR INTERNAL COMBUSTIONENGINES CONTAINING AS AN ESSENTIAL CO-ACTIVE INGREDIENT AN ADDITIVE PEREACH LITER OF FUEL CONSISTING OF ABOUT 0.5-15 MG. OF ZINC IN THE FORM OFZINC NAPHTHENATE, ABOUT 0.5-25 MG. OF COPPER IN THE FORM OF COPPERNAPHTHENATE AND LEAD IN THE FORM OF LEAD NAPHTHENATE IN AN AMOUNT EQUALTO AT LEAST TWO TIMES THE TOTAL OF THE ZINC AND COPPER CONTENT, THETOTAL AMOUNT OF ZINC, COPPER AND LEAD BEING NOT MORE THAN 200 MG. PERLITER, AND ALSO CONTAINING A MEMBER SELECTED FROM THE GROUP CONSISTINGOF BROMINATED AND CHLORINATED BENZENE AND ETHYLENE IN AN AMOUNTSUFFICIENT FOR AN ABOUT 10100% BROMINATION AND AN ABOUT 20-200%CHLORINATION, RESPECTIVELY, OF SAID COPPER, ZINC AND LEAD.